In the global industry of international trade goods movement, the primary method of shipping involves the use of transoceanic ships, trains, and trucks. Marine terminals have been the primary facilities in which ships specifically built to deliver containers are moored under gantry cranes specifically designed to transfer containers and cargo onto and off these container ships. Pier side gantry cranes, massive in structure, are aligned parallel and adjacent to the waters edge and are positioned with the crane booms outstretched over the water. This area of crane position and the area of land immediately under and surrounding these cranes is referred to on the west coast longshoreman's vernacular as the highline.
The large land area immediately further inland is typically surfaced by blacktop, concrete or firm paving which create a surface upon which vehicles transport containers to and from the pier side gantry crane area highline. This large land area immediately further inland is designated for the temporary storage, stacking or parking via wheeled chassis of containers and is referred to as the container yard. Typically, another large flat paved surface area of land within the marine terminal usually adjacent to the container yard area is referred to as the on dock rail yard. This section of land is dedicated to containers assigned to intermodal transfer via train. The gate is the entrance and egress area of the marine terminal whereby trucks enter and leave the facility carrying the containers whereby the use of a wheeled chassis or flatbed is required to make a container mobile.
For decades, attempts have been made to invent facilities, apparatus, or automated storage and retrieval systems specifically designed to improve the utility of intermodal container transfer currently practiced by railroads, conventional marine terminal operators, and stevedores.